Operating temperatures of gasses in and passing from combustors of gas turbine engines are typically quite high, requiring cooled liners in the combustors and downstream thereof to avoid damage to the internal parts of the engines. Cooling is typically provided by a compressor upstream of the combustor. To maximize engine efficiency, it is desirable to use the minimal amount of cooling air necessary to maintain the integrity of the liners and not to allow any cooling air leakage.
Leakage may occur between mating or adjacent components and seals. Tight tolerances between such mating or adjacent components are typically employed to minimize such leakage.